Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Dertli, Enes(117)
- Kaya, Yunus(51)
- Şahin, Engin(48)
- İspirli, Hümeyra(47)
- Özen, Soner(46)
- Şenay, Volkan(45)
- Pat, Suat(44)
- Can, Zehra(39)
- Bayraktar, Bülent(37)
- Bayram, Sinan(37)
- Korkmaz, Şadan(36)
- Cuce, Erdem(35)
- Ecem Bayram, Nesrin(33)
- Kutlu, Naciye(33)
- Yilmaz, Mustafa Tahsin(32)
- Artar, Musa(31)
- Ertugrul, Mehmet(30)
- Öner, Erdal(30)
- Ayata, Ümit(29)
- Hasar, Ugur Cem(29)
- Esmer, Yusuf(28)
- Mercan, Emin(27)
- Cuce, Pinar Mert(26)
- Özdemir, Akın(25)
- Çolak, Murat(24)
- Bayram, Ozkan(23)
- Kamiloğlu, Aybike(23)
- Sert, Durmuş(22)
- Ayazoglu, Rabil(21)
- Abdioglu, Murat(20)
- Bayram, Nesrin Ecem(20)
- Kadakal, Mahir(20)
- Kara, Yakup(20)
- Kizil, Hamit Emre(20)
- Tozlu, Alperen(20)
- Birinci, Ahmet(19)
- Gerçek, Yusuf Can(19)
- Battal, Fetullah(18)
- Dirican, Ebubekir(18)
- Ergün, Mustafa(18)
Yayınlar
- MakaleAçık Erişim2020Scopus SJRQ1Portable infrared sensing technology for phenotyping chemical traits in fresh market tomatoes
Akpolat, Hacer; Barineau, Mark; Jackson, Keith A.; Aykas, Didem P.; Rodriguez-Saona, Luis E.
Our objective was to develop predictive regression algorithms based on infrared spectroscopy to screen for selected quality traits directed at optimizing the selection capabilities of fresh market tomatoes. Fresh tomato (681) samples were harvested from multiple locations (Florida, Virginia, California and South Carolina) during the 2016 and 2018 seasons at various ripening stages. Spectra were collected by transmittance and attenuated total reflectance (ATR) either from the tomato surface or juice. Reference methods included soluble solid content, titratable acidity, sugars, organic acids, and lycopene. Partial least squares regression using surface spectra showed good correlation for lycopene and ascorbic acid (rcv>0.9) but modest correlation coefficients (rcv 0.54–0.80) for all other traits, while juice spectra gave high correlation coefficients (rcv>0.94) and excellent predictive performance (RPD range 3–10) for all quality traits except ascorbic acid (rcv>0.79). Multiple quality traits were simultaneously determined by using a single drop of sample providing fast (<1 min) measurements and minimal sample preparation based on unique spectral fingerprints.
AtıfScopus17WoS15OpenAlex19
İncele - MakaleAçık Erişim2020Scopus SJRQ1Diversity and functional characteristics of lactic acid bacteria from traditional kefir grains
Purutoğlu, Kübra; İspirli, Hümeyra; Yüzer, Mustafa Onur; Serencam, Hüseyin; Dertli, Enes
Traditional kefir grains were collected from distinct parts of Turkey, and their microbial profile was determined. A wide bacterial biota was observed formed by distinct lactic acid bacteria (LAB) in which Lactococcus lactis strains appeared to be dominant. Yeast species were also identified in kefir grains. Significant levels of antifungal and antibacterial activities were monitored in kefir isolates. All tested LAB produced an exopolysaccharide (EPS) containing glucose and galactose, and some strains formed a fructan-type EPS. Importantly, low levels of antibiotic resistance were observed among the kefir isolates.
AtıfScopus37WoS32OpenAlex44İncele - MakaleAçık Erişim2020Scopus SJRQ4Analysis of shear walls for a suitable opening
Can, Ömer; Tayfur, Bilal
The main purpose of shear walls in reinforced concrete structures is to resist the lateral forces affecting the structure. However, the openings created for architectural reasons significantly change the behaviour of the shear wall and cause short column formation and sudden collapse of the structure due to the openings on them. In this study, opening shear walls were analysed analytically. Twenty-nine different frames were selected and analysed according to predetermined parameters such as frame height, frame spacing, shear wall thickness, opening/frame height ratio, concrete flexibility, modulus and moment of inertia of frame columns. In this context, a total of 5200 linear elastic analyses were performed. The analysis was carried out on seven different parameters. As a result of the analysis, it has been found that there is a non-linear relationship between the opening width and the stresses in the columns, and a nonlinear relationship is predicted that it can directly trigger short column formation.
AtıfScopus1WoS1İncele - Kitap BölümüYalnız künye2020Interactive effects of remittances and financial development on Turkey's economic growth
Ari, Yilmaz Onur
Labor migration from underdeveloped and developing countries to developed countries has gained great importance, especially with the acceleration of globalization since the 1980s. The remittances that migrants earn by working in the receiving countries and send to their families have become an important tool for fighting against poverty and supporting economic growth.Migrant remittances, which are more stable than other financial sources, became a primary source of foreign exchange for supporting economic growth of developing countries by financing the current account deficit, reducing poverty, increasing consumption expenditures, and increasing household savings and investments. Remittances, which are an important financial source for developing countries, affect the economic growth in the remittance-receiving country positively or negatively. There is no consensus in the literature about the effect of remittances on economic growth.Remittances take an important place for lowering poverty and supporting economic growth because Turkey is a developing country. In this study, I analyzed a historical background of remittance flows to Turkey. By looking back at the literature, I tried to correlate Turkish remittances to Turkish financial sector development.
- MakaleAçık Erişim2020Evaluation of waste management using clustering algorithm in megacity Istanbul
Guleryuz, Didem
Industrialization and urbanization are increasing with the effect of globalization worldwide. The waste management problems are rising with the rising population rate, industrialization, and economic developments in the cities, which turned into environmental problems that directly affect human health. This study aims to examine waste management performance in the districts located in the city of Istanbul. To ensure that the districts are clustered in terms of the similarities and differences base on waste management. On this occasion, the authorized unit managers of the districts in the same cluster will be able to establish similar management policies and make joint decisions regarding waste management. In addition, the division of districts into clusters according to the determining indicators can provide information about the locations of waste storage centers. Also, these clusters will form the basis for the optimization constraints required to design appropriate logistics networks. Waste management performance of 39 districts in Istanbul in 2019 was compared by taking into consideration domestic waste, medical waste, population, municipal budget, and mechanical sweeping area. The data were obtained from The Istanbul Metropolitan Municipality (IMM) and Turkey Statistical Institute (TURKSTAT). One of the non-hierarchical clustering methods, the K-means clustering method, was applied using IBM SPSS Modeler data mining software to determine the relations between 39 districts. As a result, the waste management performance of the districts was evaluated according to the statistical data, similarities and differences were revealed by using the determined indicators.
AtıfScopus12OpenAlex11TR Dizin1
İncele - MakaleYalnız künye2020Scopus SJRQ2Investigating the Optimum Model Parameters for Casting Process of A356 Alloy: A Cross-validation Using Response Surface Method and Particle Swarm Optimization
Şensoy, Abdullah Tahir; Çolak, Murat; Kaymaz, Irfan; Dispinar, Derya
This study aimed to determine the optimal casting parameters for the maximum fluidity of A356 alloy. Gravity die cast method was used. For this purpose, central composite design (CCD) was performed. The input parameters and their limits for the trial design were selected as pre-heating temperature (100–400 °C), casting temperature (680–760 °C), and cross-sectional thickness (1–10 mm). Using the CCD-based simulation results of the feed distance, a highly correlated full-quadratic regression equation was obtained with the highest R2 (0.99), which then was used as the objective function for the particle swarm optimization (PSO) process. The highest value of the response parameter, flow distance, reached up to 491.19 mm when the input parameters were selected as 400 °C, 760 °C and 10 mm, respectively. The sensitivity analysis has shown that the most effective parameter on the fluidity is the cross-sectional thickness. The response surface method (RSM)-based optimization results have been also validated using the PSO method. Although the higher temperatures have been found to result in better fluidity, there may be some drawbacks to working at higher temperatures such as energy cost and mould life. To determine the optimum input parameters, the RSM model suggested in this study can be modified for any type of casting process. Moreover, especially for a complex-shaped part, the manufacturer can be advised regarding operating conditions such as pre-heating and casting temperatures.
AtıfScopus11WoS9OpenAlex13İncele - MakaleAçık Erişim2020Tracking the pre-service teachers’ development of communicative skills and their beliefs towards communicative approach
Kurnaz, Yıldıray; Özbay, Ali Şükrü
Concerns about the purpose of developing communicative skills in English teaching and approaches to overcome these concerns have always had an important place in language teaching. In this context, besides the fact that teachers‟ roles are important, their beliefs about the approach have a profound influence on their professional achievement. In this regard, the aim of the present study was to determine Turkish English as a Foreign Language (EFL) student teachers‟ beliefs about developing their communicative skills with the communicative approach in Turkish context. The data obtained through Pre-Service Teacher Beliefs Questionnaire, in which 445 participants took part, and focus group interviews with 28 participants at several times and places were analysed by quantitative and qualitative data analysis methods respectively. As a result of the analysis, it was found that EFL student teachers generally had positive attitudes towards improving communicative skills of their prospective students with communicative approach; however, it was difficult for this approach to work properly in Turkey and in Turkish education system due to various reasons. In addition, it was found that EFL student teachers' self-efficacy beliefs were correlated with their attitudes towards the approach, and that many sub-factors such as second language proficiency also had an influence on the attitudes. Lastly, these findings were found to be significantly different according to the departments (ELL, ELT) rather than age and gender.
AtıfScopus3OpenAlex4İncele - MakaleAçık Erişim2020Scopus SJRQ3Influence of lactobacillus reuteri on internal organ weight, performance and meat quality of Japanese quail (Coturnixcoturnix japonica) under heat stress; [Einfluss von lactobacillus reuteri auf das gewicht der inneren organe, die leistung und die fleischqualität Japanischer Wachteln (Coturnix coturnix japonica) unter Hitzestress]
Tekce, E.; Bayraktar, B.; Aksakal, V.; Dertli, E.; Kamiloğlu, A.; Çinar Topçu, K.; Kaya, H.; Takma, C.; Yasulergezer, N.
In the present study, the effects of Lactobacillus reuteri E81 (LRE) supplemented at different doses (200, 400 and 600 mg/kg) into the diets on performance, meat quality and internal organ weights of Japanese quail (Coturnixcoturnix japonica) were investigated under heat stress (HS) conditions (37°C). For the experiments, 448 one-day old quails were used. Seven days of training (physical exercise) and a 35-day fattening period were applied. On day 7 of the trial, 8 groups [4 under control temperature of 25°C (CT): control (C), LRE-200, LRE-400 and LRE-600 and 4 under HS: control (HSC), SLRE-200, SLRE-400 and SLRE-600] were formed, each group consisting of four replicates with 14 quail each. At the end of this study, the CT group fed 400 mg/kg LRE showed the best performance results, whereas no effect was found for groups under HS in comparison to the control group (HSC). Samples taken on the 21st and 42nd day revealed that addition of probiotics in the CT and HS groups induced no effect on weight of the internal organs (p > 0.05). Analysis of meat quality on the 21st day showed that LRE caused an increase in pH in both the HS and CT groups. Further, 400-mg/kg LRE supplementation induced an increase in thiobarbituric acid reactive substances (TBARS) in the group under HS. In the CT groups on day 42 no effect of LRE was found on colour parameters or on the TBARS value, except for a decrease in the pH value in the LRE supplemented groups compared with the control. In HS groups a decrease in the L* value and an increase in the TBARS value was found compared to CT groups (p < 0.05), but there was no effect on other colour parameters or pH value. In conclusion, in the present study supplementation of different doses of LRE E81 to quail diets had no effect on performance, internal organ weight or meat quality under HS.
AtıfScopus2WoS2OpenAlex6İncele - MakaleAçık Erişim2020Scopus SJRQ3Determination of the impact damage threshold point of composite material using fuzzy-base taguchi method
Erbayrak, Seda; Erbayrak, Engin
In this study, the impact damage threshold point of composite materials was determined using the optimum design parameters obtained from the Fuzzy Based Taguchi Method (FBTM). It is known that both Taguchi and Fuzzy methods provide optimization of design parameters yet, in Taguchi method, optimization of design parameters is not sufficient in solving multi response optimization problem. Therefore, Fuzzy Logic system was combined with the Taguchi system for working out the multi-response optimization problem. In this study, the low velocity impact damage analyses were performed in an LS-DYNA 3D explicit finite element program. ASTM D7136/D7136M standard was used during the low velocity impact analyses. In explicit finite element analyses, contact algorithms were executed to observe better damage zone shapes. Furthermore, the control parameters (termination and computation time step) were tuned to provide perfect correlation with the force-energy-time histories. The study concluded that Fuzzy Based Taguchi Method (FBTM) is much more capable of optimizing the design parameters that predict the impact damage threshold point of the composite material.
AtıfScopus11İncele - MakaleAçık Erişim2020Scopus SJRQ2Magnetic force and stiffness performances of Maglev system based on multi–surface arrangements with three-seeded bulk YBaCuO superconductors
Ozturk, K.; Abdioglu, M.; Karaahmet, Z.
We have designed a multi–surface HTS (high temperature superconductor with three seeded bulk YBaCuO) Maglev system by increasing the YBaCuO number while decreasing the PM number in HTS–PMG system to enhance the loading capacity and stability of the superconducting Maglev system while reducing the fabrication cost. By this study, a detailed investigation on the magnetic levitation force, guidance force, magnetic stiffness and cost analysis of the multi–surface HTS Maglev system has been carried out for the first time. In this study, it is determined that the multi–surface YBaCuO–PMG arrangements are superior to the single–surface arrangements with respect to the loading capacity and especially the movement stability of Maglev systems together. Additionally, it is seen that the using of the multi–surface YBaCuO–PMG arrangement reduces the fabrication cost of the Maglev systems as 42.0% for 1000 km magnetic rail while increasing of the levitation force efficiency as 43.4% and this emphasizes the advantage of multi–surface arrangements to the classical single–surface ones. The obtained results can contribute to the researchers working on Maglev and have a capability to increase the usage potential of Maglev systems in commercial applications because of both the loading capacity and stability of Maglev systems can be enhanced together with reducing the fabrication cost without any loss in levitation performance.
AtıfScopus19WoS18OpenAlex21İncele - MakaleYalnız künye2020Scopus SJRQ4Candida zeylanoides as whole-cell biocatalyst to perform asymmetric bioreduction of benzophenone derivatives
Şahin, Engin
Candida zeylanoides P1 was investigated as whole cell biocatalyst for the bioreduction of biaryl prochiral ketones into chiral carbinols, which can be used as pharmaceutical intermediate. Bioreduction of different biaryl ketones was carried out to their corresponding chiral biaryl carbinols such as (S)-(4-chlorophenyl) (phenyl) methanol (2a), which can be used in the synthesis of L-cloperastine drug, with antitussive, antiepidemic activity and bronchial musculature relaxant characteristics, in gram scale, enantiopure form (>99%) and excellent yields. The selectivity of C. zeylanoides P1 in enantioselective reduction of biaryl ketones was not affected by the steric and electronic effects of substrates. The current method demonstrates an encouraging green chemistry approach for the production of biaryl secondary chiral alcohols of pharmaceutical importance in mild, inexpensive and environmentally friendly process. The present study has many benefits since this yeast biocatalyst were successfully applied bioreduction of structurally bulky prochiral substrates, which cannot be reducted by chemical catalysis.
AtıfScopus10WoS9OpenAlex10İncele - MakaleAçık Erişim2020Scopus SJRQ2Graphene/polyaniline nanocomposite as platinum-free counter electrode material for dye-sensitized solar cell: its fabrication and photovoltaic performance
Bayram, Ozkan; Igman, Erdal; Guney, Harun; Demir, Zeynep; Yurtcan, Mustafa Tolga; Cirak, Cagri; Hasar, Ugur Cem; Simsek, Onder
In this study, it was aimed to produce graphene/polyaniline nanocomposite thin films as counter electrode materials by PECVD system and to determine the photovoltaic performances of these counter electrodes in dye-sensitized solar cells (DSSCs). Graphene/polyaniline counter electrode (GPCE) material was produced in two different steps. Firstly, a single-layer and multilayer graphene thin films were produced on the fluorine-doped tinoxide (FTO) substrates. Then, polyaniline (PANI) thin films were grown on each graphene thin films using plasma polymerization technique, and eventually the production of the graphene/PANI nanocomposite was completed. The fabricated graphene/PANI nanocomposites were used in place of platinum (Pt)-counter electrode which is widely used in DSSCs and the photovoltaic performance of these counter electrodes was investigated. The DSSCs consisted of titanium dioxide (TiO2) nanotube photoanode, N719 dye, iodolyte liquid electrolyte, and graphene/PANI nanocomposite counter electrode. I–V measurements were carried out in order to calculated photoconversion efficiency (PCE) and it was found that the these efficiency of GPCEs changed between 0.56 and 1.36% according to the number of graphene layers. The photovoltaic performance of DSSC, consisting of TiO2 nanotube photoanode and Pt-counter electrode was 1.1%.
AtıfScopus33WoS25OpenAlex29İncele - MakaleYayıncıda açık erişim2020Scopus SJRQ2Response of Japanese quails (Coturnix coturnix japonica) to dietary inclusion of Moringa oleifera essential oil under heat stress condition
Tekce, Emre; Bayraktar, Bülent; Aksakal, Vecihi; Dertli, Enes; Kamiloğlu, Aybike; Çinar Topcu, Kübra; Takma, Çiğdem; Gül, Mehmet; Kaya, Hacer
The present study was aimed at investigating the effects of the dietary use of different doses of Moringa oleifera essential oil (MOEO) on performance parameters, internal organ weights and meat quality in Japanese quails (Coturnix coturnix japonica) exposed to Heat Stress (HS). For this purpose, 320 male day-old quail chicks were used. Seven days of preliminary (physical exercise) and a 35-day fattening period were applied. The animals were divided into 8 groups, each including 40 animals according to temparature (C: 25 °C and SC: 37 °C) and dietary doses (C, 200, 400 and 600). Each group was divided into 4 subgroups, each comprising 10 animals. The consequences of this study showed that, in the stress-free (HSF) groups, while all of the different doses of dietary MOEO positively affected growth performance, feed intake and feed efficiency, in the HS groups, similar positive effects were observed with the use of 200 ppm of dietary MOEO. While no effect was detected on internal organ weights on Days 21 and 42 in the HSF and HS groups, a dose-dependent increase was determined in the intestinal pH value on day 42 in the HS group (p <.05). Additionally, in the analysis of meat quality on the 21st and 42 days compared to the controls, no effect was observed on the meat colour parameters value and TBARS level in the HS and HSF groups. Based on the consequences of this study, it is considered that, MOEO could be used as an alternative product in poultry, at a dose of 200 ppm, to reduce the detrimental effects of HS.HIGHLIGHTS Temperature stress, performance parameters and serious problems in the health of poultry. Moringa olifera helps regulate performance parameters in poultry exposed to heat stress. Since the addition of Moringa oleifera to the diets does not affect the organ weight and meat quality in 21 and 42 days, it does not cause any negative effects for the consumer.
AtıfScopus17WoS17OpenAlex19İncele - MakaleAçık Erişim2020Scopus SJRQ2Effect of the addition of essential fatty acid mixture to the drinking water of the heat stress broilers on adipokine (Apelin, BDNF) response, histopathologic findings in liver and intestines, and some blood parameters
Bayraktar, Bülent; Tekce, Emre; Aksakal, Vecihi; Gül, Mehmet; Takma, Çiğdem; Bayraktar, Sevil; Bayraktar, Fatma Gülten; Eser, Gizem
The purpose of this study was to examine the effect of adding an essential fatty acid mixture (EOM; Eucalyptus globulus Labill, thymus vulgaris, Cymbopogon nardus, and Syzygium aromaticum) to the drinking water in the heat stress broilers on the adipokine (Apelin, BDNF) response, the histopathologic changes in liver and intestines, and some biochemical parameters. This study lasted for a total of 42days, including the physical exercise period (7days) and the fattening period (35days). A total of 400 Ross 308 male broilers (1-d-old) were randomly divided into 8 groups (50 animals per group), each of which was exposed to various conditions of temperature (C: 22°C and SC: 36°C) and treatment dose (C, 250, 500 and 750mL/1000 L). Each group was divided into 5 subgroups, each comprising 10 animals. In the stress-free groups, whereas the Apelin level linearly decreased, the BDNF level linearly increased. In histopathology, the liver tissue was found to be normal in all groups whereas the duodenum villi length was found to increase in the group of 750mL/1000 L. No statistically significant difference was found between the stressed groups and the non-stressed groups in terms of VLDL, Glucose, Total bilirubin, ALT, and TG (p >.05). While Apelin level increased in the stressed groups, the BDNF level increased in the group of 250mL/1000 L. In the histopathological examination, a small amount of coagulation necrosis was detected in hepatocyte, a diffuse hydropic degeneration was observed in hepatocytes, and finally a dilatation and hyperaemia were seen in sinusoid in the groups of EOM-500mL/1000 L and EOM-750 m/1000 L compared to the control group. Whereas there was no difference between the group of EOM-250mL/1000 L and the control group in terms of duodenum villa length, there was a significant decrease in other groups (p <.00). In conclusion, this study showed that adding 250mL/1000 L of EOM to the drinking water had a positive effect on the serum levels of Apelin and p-BDNF in the groups exposed to stress (p <.05).HIGHLIGHTS Heat stress results in serious annual economic losses in the poultry industry. Essential oil fatty mix acids have positive effects on poultry health. Apelin and BDNF may be a protective factor against deleterious consequences of chronic exposition to heat stress.
AtıfScopus12WoS9OpenAlex10İncele - MakaleAçık Erişim2020Scopus SJRQ2Phy-X / PSD: Development of a user friendly online software for calculation of parameters relevant to radiation shielding and dosimetry
Şakar, Erdem; Özpolat, Özgür Fırat; Alım, Bünyamin; Sayyed, M.I.; Kurudirek, Murat
A user friendly online Photon Shielding and Dosimetry (PSD) software available at https://phy-x.net/PSD has been developed for calculation of parameters relevant to shielding and dosimetry. These parameters include linear and mass attenuation coefficients (LAC, MAC), half and tenth value layers (HVL, TVL), mean free path (MFP), effective atomic number and electron density (Zeff, Neff), effective conductivity (Ceff) energy absorption and exposure buildup factors (EABF, EBF). The software can generate data on shielding parameters in the continuous energy region (1 keV-100 GeV). Also, some well-known radioactive sources (22Na, 55Fe, 60Co, 109Cd, 131I, 133Ba, 137Cs, 152Eu and 241Am) along with their energies and some characteristic (K-shell) X-ray energies of Cu, Rb, Mo, Ag, Ba and Tb elements are available in the software and can be selected by the user. Thus, one can obtain the shielding parameters at photon energies available for the predefined energies. Moreover, another parameter relevant to shielding i.e. the fast neutron removal cross section (FNRCS) can be calculated for a compound or a mixture using this software. The software is freely available online after having registered to the Phy-X platform.
AtıfScopus2019WoS1977OpenAlex2133İncele - MakaleAçık Erişim2020Scopus SJRQ3Examination of the metaphors of classroom and social sciences teacher candidates related to the concept of direction
Kuzey, Memet; Değ Irmenci, Yavuz
The aim of this research is to demonstrate the perception of the direction concept of the prospective teachers in the departments of classroom education and social sciences education through metaphors. For this purpose, the research was conducted in 2018-2019 academic year with a total of 174 teacher candidates studying in social sciences teaching and elementary education departments of the faculty of education of a state university in Turkey. One of the approaches to qualitative research, the phenomenology (phenomenology) design, was used in the study. The views and thoughts of the working group on the concept examined "the concept of direction... like/is similar to because... "collected by interview form consisting of his statement. Content analysis technique was used in the analysis of data. According to the findings of the study, participants developed a total of 81 valid metaphors for the concept of direction. These metaphors have been collected under 11 different categories. As a result of the study, the most preferred metaphors for the direction concept of the participants were the words Sun, Pole Star, Road, Compass, book and clock.
- MakaleAçık Erişim2020Optimization of exopolysaccharide production of Lactobacillus brevis E25 using RSM and characterization
Ermis, Ertan; Poyraz, Ecem; Dertli, Enes; Yilmaz, Mustafa Tahsin
Response surface methodology was used to determine the exopolysaccharide production of Lactobacillus brevis E25. The effects of three variables, temperature (30, 36 and 42 °C), incubation time (18, 33 and 48 h) and initial pH of growth medium (4.5, 5.5, and 6.5) were studied. Under optimum growth conditions, the amount of exopolysaccharide derived from Lactobacillus brevis E25 ranged from 10 to 35 gL-1. The size of EPS molecules ranged from 105 to 107 Da. Infra red spectrum analysis showed characteristics absorption peaks indicating the presence of-OH, C=O and C-H groups. Furthermore, only glucose was detected as monosaccharide in exopolysaccharide structure, revealing that the structure of exopolysaccharide is a homopolymeric glucan type. Based on the differential scanning calorimeter thermograms, exopolysaccharide’s melting temperature was observed around 116 °C.
AtıfScopus18OpenAlex18İncele - MakaleYalnız künye2020Scopus SJRQ4Production of enantiopure chiral aryl heteroaryl carbinols using whole‐cell Lactobacillus paracasei biotransformation
Şahin, Engin
Aryl and heteroaryl chiral carbinols are useful precursors in the synthesis of drugs. Lactobacillus paracasei BD87E6, which is obtained from a cereal based fermented beverage, was investigated as whole cell biocatalyst for the bioreduction of different ketones (including aromatic, hetero-aromatic and fused bicyclic ketone) into chiral carbinols, which can be used as a pharmaceutical intermediate. The study shows that bioreduction of aryl, heteroaryl and fused bicyclic ketone (1–5) to their corresponding chiral carbinols (1a–5a) in excellent enantioselectivity (>99%) with high yields. This study gave the first example for an enantiopure production of (S)-6-chlorochroman-4-ol (3a), which has many antioxidant activity, by a biological method. For asymmetric bioreduction of other prochiral ketones, these results open way to use of L. paracasei BD87E6 as biocatalysts. Also, the present process shows a hopeful and alternative green synthesis for the production of enantiopure carbinols in a mild, inexpensive and environmentally friendly process.
AtıfScopus21WoS18OpenAlex20İncele - MakaleYalnız künye2020Scopus SJRQ2Operational Matrix by Hermite Polynomials for Solving Nonlinear Riccati Differential Equations
Kosunalp, Hatice Yalman; G¨ulsu, Mustafa
This paper studies the potential to ensure a numerical solution of nonlinear Riccati differential equations with an effective method, namely operational matrix which is derived by Hermite polynomials with the sense of Caputo derivative. In order to solve the Riccati dif- ferential equations, the complete problem is simplified with the oper- ational matrix obtained. To achieve this goal, the proposed approach converts the fractional differential equations (FDEs) into a set of alge- braic equations. We then construct a matrix with the algebraic equa- tions and extra equations extracted from initial conditions. Therefore, we achieve the solution by solving these algebraic equations given in a matrix sense. In order to show the efficiency of the proposed idea, we show a number of illustrative examples in which the results confirm the applicability of the suggested approach.
AtıfScopus2İncele - Kitap BölümüYalnız künye2020The Relationship of financial development and export; the case of Turkey: A literature review
Sayar, Ramazan
During the global financial crisis in 2008, the world trade experienced a large and severe collapse. Between 2008 and 2009, world exports and exports in Turkey decreased by 16% and 22%, respectively. The recent research has shown that the slowdown in global demand and tight financing conditions are the main factors behind this drop in exports. Auboin (2009) has stated that the 10%-15% decline in international trade after the global financial crisis may be due to the decline in commercial finance. In addition, the decline in commercial finance is particularly important for developing countries that have many sectors dependent on external financing. This study examines the reasons of the decline in exports in the world especially in Turkey during global financial crisis and assesses whether the financing constraints have contributed to this collapse.This study considered as a literature review consists of theoretical framework of the relationship between export and export financing. In order to show whether there is an effect of financing in international trade, firstly, research on the financial models is included in the classical models of international trade that show the dependence of international trading companies to financing. Secondly it has been utilized studies that analyzing of empirical evaluations of the effects of the external trade firms' dependence on external financing.